I can't or won't answer that as its your fish and I would hate to be the one who told ya it was "safe" to do it in all in one day. I have never done it all in one day. Its always been 10 days or later before I added fish and even then its never been more then 5 or so fish and then I would stock slowly from there. In the tank I have now I have 10 fish in a 10 gallon soil tank after several months.
Also be aware there are risk in doing a soil tank such as anaerobic bacteria producing hydrogen sulfide more so then in gravel or just sand tank.

I cant help but pick up on that the soil can and will produce ammonia and rites correct? along with much more hydrogen sulfide. in ur tank you gave it 10 days before adding fish correct? and once you added fish it was 5 at a time then slowly back to 10 from there. did you happen to use a established filter to assist with the spikes?

I just don't have the means to keep my fish out of the tank for more then a day but I am very interested into this whole soil thing its atelast worth a shot.

In the current setup I gave it 10 days before adding before adding 4 fish. Yes it was with a seeded filter. I think a month or so I added 9 a total of 11 (I had some deaths but not due to my water or the tank being a soil tank). I never once saw a spike but keep in mind I have know others who have. I may (call it luck or whatever.) have been lucky. You can see spikes in ammonia and or nitrites/nitrates. Generally after the initial spike is going you generally won't see another but I suppose you could.

From your journal I wouldn't really consider your tank heavily planted, especially not in regards to all the super fast growing stem plants you would have to use to add fish back in the same day.

I would avoid doing this if you only have a single day. You have a seeded filter, but that's not the whole story. A lot of bacteria occurs in the substrate as well and you will be removing all of that. Just changing substrate can cause mini cycles and on top of that you'd be adding a possible source of ammonia. I just don't think it would be safe.

I did seem the pictures and the plants look healthy. In my mind at least it's medium planted, maybe I just have a warped sense of what is heavily planted. I've never had a sword plant and have no clue how fast they grow. Usually when you see about Walstad tanks it's the faster growing stems like watersprite, or some Hygrophilas, Rotalas, Luwigia repens, Hornwort, etc.

I would just stick with the root tabs and Comprehensive given the time restraint. It's working for you, so why change it? Eventually the CO2 is going to stop being produced if the fact that after 9 months to a year the bubbling stops is any indication.

What do you mean by struggling with nitrogen? As in too many nitrates? Soil won't help that.

not enough, there are some little brown spots on a few of the leafs while the whole leaf stays green n def right?

I'm not so sure about this. I have swords in several tanks, and in the ones with better lighting, they're doing great - my nitrate levels are typically very low - 7.5ppm at the most, but most of my tanks run in the range of 2.5- 5 if not 0. . . *shrugs* Your lighting is higher than ANY of my tanks, though, so it could be. . .but is it possible that there is another reason why your swords are having these issues?

I want to experiment with a dirty tank, too - but I'm REALLY leery about doing so with any fish involved. I'd suggest you find another way. . . it's just too dangerous! I'm planning to set up a 10g, and just let it run for a while doing loads of water tests, until I'm sure it's safe for my babies. . .

Definitely second Ao's recco on the book. Even if you don't follow her method, it's a good book to read.